The objective of this contract is to attempt to define the correlates of immune protection against HIV by establishing the "Correlates of HIV Immune Protection Laboratory." It is essential to understand what immune responses might provide protection against diverse strains of HIV in vaccines. It is also essential to determine whether incomplete immunity-- immunity that does not protect from primary infection--still has an impact on the course of HIV infection and disease development. The work to e accomplished requires diverse expertise in HIV virology, immunology, and molecular biology. These assessments in vaccines must be timely and highly coordinated. In addition, subjects in natural history cohorts will be evaluated for similar parameters. Individuals that are either healthy long-term survivors of HIV infection, or individuals at high risk of exposure to HIV but uninfected are of particular interest for study under the scope of this contract. The contract will provide in-depth evaluation of the HIV-specific humoral and cellular immune responses of infected vaccines, natural history cohort study subjects, and appropriately selected controls. In addition, this laboratory will isolate and characterize the genotype and phenotype of the infecting HIV. Project coordination provided in the contract will include epidemiological and biostatistical evaluation of the studies performed, in cooperation with the AIDS Vaccine Evaluation Group and the natural history cohorts, as well as the day-to-day tracking of samples and data from those samples.